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1883 eruption of Krakatoa
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The 1883 eruption was one of the deadliest and most destructive volcanic events in recorded history. At least 36,417 deaths are attributed to the eruption, significant additional effects were also felt around the world in the days and weeks after the volcanos destruction. In the years before the 1883 eruption, seismic activity around the Krakatoa volcano was intense, beginning May 20,1883, steam venting began to occur regularly from Perboewatan, the northernmost of the islands three cones. Eruptions of ash reached an altitude of 6 km and explosions could be heard in New Batavia 160 km away. Activity died down by the end of May, and there was no recorded activity for several weeks. Eruptions at Krakatoa started again around June 16, with loud explosions, on June 24, a prevailing east wind cleared the cloud, and two ash columns could be seen issuing from Krakatoa. The seat of the eruption is believed to have been a new vent or vents that formed between Perboewatan and Danan, the violence of the ongoing eruptions caused tides in the vicinity to be unusually high, and ships at anchor had to be moored with chains. Earthquakes were felt at Anyer, Banten, and ships began to report large pumice masses to the west in the Indian Ocean, on August 11, a Dutch topographical engineer, Captain H. J. G. Ferzenaar, investigated the Krakatoa islands. He noted three major ash columns, which obscured the western part of the island, and steam plumes from at least eleven other vents, mostly between Danan and Rakata. When he landed, he noted an ash layer about 0.5 m thick, and he advised against any further landings. The next day, a passing to the north reported a new vent only a few meters above sea level. By August 25, the Krakatoa eruptions intensified, at about 13,00 on August 26, the volcano went into its paroxysmal phase. By 14,00, a cloud of ash could be seen 27 km high. At this point, the eruption was virtually continuous and explosions could be heard every ten minutes or so, ships within 20 km of the volcano reported heavy ash fall, with pieces of hot pumice up to 10 cm in diameter landing on their decks. Between 18,00 and 19,00 hours, a tsunami hit the shores of Java and Sumatra. On August 27, four enormous explosions occurred, at 5,30 am, the first explosion was at Perboewatan, triggering a tsunami heading straight to Telok Betong, now known as Bandar Lampung. At 6,44 am, Krakatoa exploded again at Danan, the third explosion has been reported as the loudest sound heard in historic times. The loudness of the blast heard 160 km from the volcano has been calculated to have been 180 dB, each explosion was accompanied by tsunamis estimated to have been over 30 meters high in places